Genetics is the branch of science concerned with genes, heredity, and variation in living organisms. It seeks to understand the process of trait inheritance from parents to offspring, including the molecular structure and function of genes, gene behaviour in the context of a cell or organism (e.g. dominance and epigenetics), gene distribution, and variation and change in populations.

Microsatellite instability is genetic instability in short nucleotide repeats (microsatellites) due to a high mutation rate as a result of abnormal DNA mismatch repair. Rather than correcting errors that occur spontaneously during DNA replication, cells with impaired mismatch repair accumulate these errors. These sequences are not preserved faithfully through DNA replication and novel microsatellites are created.